Semiautomatic telegeaph tkanssiittee



June 23, 1925. v L. c. McINTOSH SEMIAUTOMATIC TELEGRAPH TRANSRITTERFiled Maya} 1921' QNTO 1/- Patented June 23, I925.

UNITED STATES. PATENT OFFICE.

LOUIS C. MCINTOSH, OF LOS ANGELES, CALIFORNIA.

sEMIAo'roMA'rIc TELEGRAPH TRANSMITTER.

Application filed-May 31,

To all whom it may concern:

Be it known that I; LOUIS Q'MoInrosrr, citizen ofthe United States andresident of Los Angeles,in the county of Los An geles and State ofCalifornia, have invented certain new and useful Improvements inSemiautomatic Telegraph Transmitters, which the following is aspecification;

This invention relates to telegraphic apparatus and particularly totelegraphic transmitters.

It is an object of the present invention to provide a semi-automatictelegraphic transmitter wherein the dash impulses are transmitted underpositive manual control and wherein the dot impulses are transmittedautomatically following an initial manual action of the dot key lever.

It is a further object of the invention to provide what is known as anautodot instrument of such construction and arrangement that thevibrator of the instrument oscillates in movements to .andfro that areat right angles. to the initiating stroke of the vibrator actuating keylever so as to substantially eliminate sensible vibrations in the keylever generated from vibrations'of the vibrator. it is an object toprovide an autodot instrument in which the dot lever and the reed of thevibrator have paths relatively at a right angle to eachother asdistinguished from various types of instruments in which the reed andthe reed actuating lever are connected and operative each withmovements, in respective paths that are parallel to each otherwith I theresult that the swing of the vibrator is reacted directly back to thekey. of the dot lever and therefore causes the vibrations of thevibrator to be strongly felt.

Another object of the invention is to provide an autodot telegraphictransmitter which may be. readily converted from a double key to a"single keyinstrument. Again an object 'is toprovide a transmitter thatmaybe readily adapted foruse as either a right hand .or a left handinstrument;

Another object is to provide a telegraphic transmitter of portablecharacter and at the same time that will remain stable when placed uponthe operators table or bench. In this connection, it is an object toprovide a telegraphic transmitter in which the operating key r y extendtransverse y In other words,

autodot 1921. Serial No. 473,630.

as to thelength of a base or frame of the transmitter and thereby tosecure and increase the steadiness of the instrument by reason of agreater leverage provided by the longer dimension of the frame or baseas compared withinstruments in'which the key projects from the narroweror end edge of the frame or base y 7 a j a A further object isftoprovide a telegraphic transmitter having a case or housmg for enclosingthe operating and adjusting elements of the instrument to pre ventunlicensed tampering with the same. and further to provide an instrumentthat is adapted to be operative in either of two positions, one beinginverted with respect to the other, as when the instrument is to beconverted from a right hand to a left hand transmitter. A further objectis to provide an instrument that can be locked against variations ofadjustment without authority. I

Other objects and advantages will be made manifest in the followingspecification of an embodiment of the invention illustrated in theaccompanying drawings,

wherein Figure 1 is a plan of the instrument. Fig. 2 is a right hand endview. U Fig. 3 is a front elevation.

. Fig. 4 is aplan of the detached vibrator organization.

Fig. 5 is an elevation of the vibrator organization.-

F 6 is a side elevation of one of the dash binding posts. 4 a

Fig. 7 is a side elevation of the dot and dash binding post.

Fig. 8 is aplan of the bridge.

detached pivot Y Fig. 9 is a plan of the dash transmitting key lever andits contiguous dash terminal post.

Fig. 10 .is a side elevation of the structure of Figurej9. Y

Fig.11 is aplan of the combination dot and dash key lever.

Fig. 12is a side elevation of the combination dot and dash key lever.

Fig. 13 is a detail of a lock case.

Fig. ll-is a perspective of the detached shell or housing.

In its illustrated embodiment the invention is shown as including aframe or primary base f such dimensions and material as to p o deufiieient We g t fi rel a stable instrument when the latter is set on atable or bench, and to secure steadiness there is provided a set ofremovable and iiiterchangeable rubber feet 3 which are suitably disposedand connected to screws or pins not shown attached to the bottom of thebase 2. The operating mechanism of the transmitter is preferably mountedupon an upper base plate 4 which is shown as of slightly less dimensionsthan the heavy base 2 and enables the interlocking application of ashell or housing 5, the lower edge of the rear wall of which is shown asprovided with lugs 6 struck inwardly and adapted to be interlocked withrear edge of a plate 4 and then swung downwardly into applied positioncovering all of the mechanism except the keys of the key levers and thehandle of the main switch.

The front wall of the housing is provided with a horizontally elongatedaperture 7 to receive and permit movement of the main switch lever Swhich is pivoted on the frame plate 4. The front wall is also providedwith upwardly extending apertures 9 and 10 to receive respectively thedash key lever D and the dot and dash or combination or autodot lever A.

A feature of the invention is to provide a transmitter which may besafely locked against unauthorized tampering and means including housing5 are provided and which may be maintained in effective or locked yposition without interrupting or interfer fering with the normaloperatlon of the transmitting levers. The housing 5, when it has beenapplied, will rest on the margin of the upper face of'the base 2 and isadapted to be locked in such position by the application of a key to akey lock L having a bolt B adapted to engage in the contiguous keeper orsocket 5, which may be formed as a part of or adapted to the housing 5as shown in Figure 14.

Connected in suitable grounded relation to the frame plate 4 is acurrent wire which is shown as'electrica'lly connected under a bindingscrew 16. The line wire 17 is connected at 18 to a binding post or screw19 which is insulated at 20 over the frame plate '4, and from thebinding screw 19 extends a connecting strip 21 which is electricallyconnected to an upwardly extending binding post or terminal 22 andfurther extending to and connecting with an 'upward 1y extending bindingpost23; both the posts 22 and 23 being insulated from the frame plate 4.

The main switch S is pivoted at 25 on the plate 4 in electricalconnection therewith and is adapted to engage a friction blade 26connected to the line binding'post 19-so as to close 'thecir'cuit.

Projecting upwardly from and preferably integral with 'the'pla'te 4 is'aseriesofpo's'ts 27, 28 and 29, and the former of these is provided witha transversely extending abutment piece 30 which may be adjustable andis secured in place by screw 31, the function of this being to serve asa brake or stop for a vibrator which includes a substantial rod 32carrying an adjustable weight-forming block 33 on its outer or swingingend.

The vibrator rod 32 is shown as disposed longitudinally of theinstrument that is, parallel to the longitudinal axis, and one end ofthe rod is connected to a light spring or reed 34 and this is connectedsolidly at one end in the arm 35 of a lever having another arm 36 whichis here shown as at right angles to the reed-carrying arm 35 and thisright-angled lever is pivoted at 37 as by pivot pins, the lower of whichmay bear in the plate 4 while the upper one is received in a contiguouslug 38 extending from a bridge piece 39 which is secured on the upperends of the columns 28 and 29.

Suitably secured to the vibrator rod 32 is a yieldable automaticallyacting dot transmitting contact 40; which is designed "to move intoengagement with the terminal 41 provided on an adjustable screw 42 inthe insulated binding post 22. The dot contact 40 is shown as providedon the free end of a substantially U-shaped spring 43, the other end ofwhich is secured to a blockor slide 44 which may be secured as by a setscrew 45 at suitable position on the vibrator rod From this it will beseen that the vibrator is designed so as to swing 'to and fro in a pathwhich is transverse to the length of the transmitter to move the dotcontact 40 into engagement with the terminal 41 conneoted to thetelegraphic line. An important feature of the invention is to providefor the operation of'the transmitter in such manner as to practicallyeliminate reaction vibrations of the vibrator back to the operators keylever. In the accomplishment of this means are provided includingL-shaped vibrator lever 3536 and an operative connection between the dotkey leveriand the vibrator. The vibrator lever arm 36 is shown asprovided with a roller 36 and this is operated by an engaging part ofthe combination autodot key lever A. This key lever is preferablyconstructed of relatively movable sections including a rear shank or bar48 engaging the roller 36 and a front section 48' which projectsforwardly through the slot 10 in the shell or housing 5 and carries adetachable finger paddle 49. This is shown as secured to the combinationlever by a screw 50 having a clamp nut 51.

The combination lever member 48 as clearly shown in Figure 12, isindicated as having a pivot pin 48, "the lower end of which bears in theplate 4 while the upper iii) end bears in the contiguous end of a screw52 mounted in the bridge 39. The combination lever section 48 ispivotally connected at 53 to the section 48 and lies parallel and inclose position thereto, the Overlapping portions of the lever sectionsbeing yieldably drawn into abutting position so that while thecombination lever may be moved bodily or as a whole on the pivot pin'48,the forward section 48 is adapted to move laterally as to the section48, so that a dash contact 54 thereon may be moved into circuit-closingposition against a contiguous and adjustable terminal 54 provided in thebinding post 23, without an accompanying movement of the rear section 48of the combination key lever. This relative yielding movement andconnection of the sections 48 and 48 is rendered possible as by means ofa compressed spring 55 surrounding a screw 56 fixed in the lever section48 iand passing freely through the lever section 48 against which thespring 55 is compressed by ad justment of a nut 57 on the screw 56.

It will be seen that the spring 55vand the screw connection 56 providefor a yielding movement of the lever section 48 away from the member 48and permits a manual operation of the combination lever to send dashimpulses by way of the binding post 23.

The combination lever A (members 48' 48) is bodily thrown in onedirection by the vibrator lever arm 3635, which is yieldingly swunginone direction by a spring 58 which may rest against a lug 59 providedon the plate 4. The action of the spring is to thrust the roller 36against the contiguous end of the lever member 48 swinging the wholecombination lever on its pivot 51 to a position which is determined byan adjustable stop screw 60 mounted in the binding post 22 and which mayhave a tip 61 of insulation to prevent short circuit.

The operation of the combination lever is therefore as follows: 7 I i intransmitting dots the combinationfinger paddle 49 is, in the normalposition of the instrument for right hand operators, given a movement tothe right as by pressure of the thumb of the right hand and this causesthe combination lever to swing a unit with the rear end of the section48 acting to swingthe lever arm 36 to the left until its movement islimited by an adjusting screw 62, Figure 1, at which moment thecombination key is brought to a stop and is held for a period of time,by the operator, according to the number of dots to be utilized intransmitting a letter or other signal. As the vibrator arm 36 engagesthe stop screw 62 the vibrator rod 32 will thus have been thrown awayfrom the stop or brake and will take up the vibratory action due to itsflexible connection as by the reed 34 with the vibrator arm 35.

While the vibrator rod 32 is oscillating the dot contact will be rapidlybrought into successive contacting engagement with the terminal 41 ofthe binding post 22 and therefore a dot or series of dots will betransmitted as determined by the length of time that the operator holdsover the combination key paddle 49. By the present con structionand'combination it is possible to use a very light and sensitive reedand also a light and quick-acting dot contact spring 43, an advantage ofthis construction being that a desired rapidity and reliability of dotimpulse actions are secured in a prac tical manner and further thetendency of the automatic mechanism to split the dot impulses is greatlyif not wholly reduced and eliminated.

The combination'lever provides not only for the sending of the dotsautomatically but. it further enables the sending of dash impulseswholly under the control of the operator, with the well-known advantagesof this manual control. The dash impulses are sent, through thecombination lever, by pressing the finger paddle 49 toward the left, inright-hand use of the instrument, during which action the lever section48 will swing away from the stationary section 48 until the dash contact54 engages the terminal 55. As soon as the pressure is released in thedash sending action the lever section 48 is instantly returned by itsspring to the clear position.

It will be observed that in the'present ar rangement the combinationlever A is disposed generally transversely to the instru ment base andit is therefore transverse to the length of the vibrator including theair-11135, the reed 34 and the rod .32; This peculiar combinationtherefore operates to prevent noticeable reaction of the vibrator, whileit is oscillating, on the finger paddle 49 of its actuating lever forthe reason that the weighted vibrator swings in a path at right anglesto the'movement of the paddle 49; the action of the vibrator beingaccomplished by the movement of the bell crank or lever' 35-36, whichconverts the right and left hand movement ofthe paddle 49 into a forwardand backward movement, with respect to the base, of the vibrator, and avery slight, if any, reaction is trans mitted through the lever section48 and its engaging lever arm 36 by the vibrator.

From the above it will be seen that the single combination autodot anddash key A may be utilized in transmitting messages consisting of dotsand dashes. Preferably the instrument is provided with a second or dashkey lever D l mit dash impulses. The key lever is provided with a pivotpin 63 bearing in the plate 4 and also in a screw bearing 64 in thebridge 39. This key lever D extends which is des ned totranstransversely across the plate substantially in parallelism with thecombination lever A. and its rear end is provided with a contactdesigned to engage a contiguous ter minal 66 on the binding post 22. Thekey lever D is yicldingly thrust so as to break contact at (36 by aspring 67 suitably sup ported on a fixed part 68. The key lever D islimited by an adjustable stop 69 when in the open position.

The key lever D is provided with a finger paddle 70 disposed opposite tothe paddle and the paddle is secured removably in place by a clamp screw71 carried by the key lover I).

A feature of the invention is to provide a two-key lever instrument thatmay be readily converted into a single lever instru ment and furtherthat may be readily converted from a right hand to a left handinstrument, and to that end if a single key instrument is desired thefinger paddle 70 is removed from the dash lever D. and is placed uponthe screw of the combination autodot lever A and clamped in place by thenut 51 so that it will then be disposed on the left hand side of thepaddle 4-9.. The operation of the autodot lever A with the two fingerpaddles applied will be precisely the same as when it carries but onepaddle 49. Since the paddle may be transferred to the autodot lever A itwill be seen that the dash lever D will be practically thrown out ofcommission by the removal of its finger paddle.

The present instrument may be readily converted into a left handtransmitter by removing the feet 3 and applying them to the topv of theshell or housing 5 and by reversing or inverting the switch S from theposition shown in Figure 2 and then inverting the entire instrument sothat the housing will be lowermost and the feet 3 thereunder applied tothe table or bench.

I have found that especially good action and clear transmission issecured by making the vibrator rod 82 of a material of light weight, andhave successfully employed rods of aluminum. lhe weight 33 mountedadjustably on the rod 32 gives a maximum stroke of the vibrator, thelength of the strokes being readily varied by the adjustment of the bodyIt will be seen that because of ample swi to weight 33 a wider gapbetween contacts 4-1 and a2 is possible and more time constant of dotcontact is secured, and therefore more current carrying capacity issocured without sacrifice of speed and with out increase of paddlestroke.

Heretofore it has been impossible to ob tain desired current carryingcapacity due to limited vibrating stroke and heavy vibrating springs andweights without undue movement of the manipulating paddle.

e senc or right hand post to serve as a brake, a

vibrator carrying an adjustable weight forming block and mounted in atransverse plane and in a line parallel with the three posts and withits free end inposition to engage the a-butn'ient, a light springconnected to the vibrator at the opposite end from the weight, an armpivotally mounted near the third post in line with the Vibrator andsolidly connected to the spring, an L- shaped arm rigid with the firstarm and at right angles thereto, a yieldableautomatical- 1y acting dottransn'iitting contact secured to the vibrator in transverse line withthe vibrator pivot, a terminal ustably mounted in opposition to thecontact, a roller at the free end of the L-shaped arm, a combinationautodot key lever mounted transversely and engaging the roller andextending forwardly and carrying a finger paddle, an adjustable stopscrew mounted through the terminal binding post at right angles to theterminal and engaging the opposite side of the combination autodot keylever from the roller, and a dash contact adjustably mounted to engagethe combination lever in front of its pivot and on the same side as theroller, the

combination lever being made in two pieces in front of the pivot, thetwo pieces being yieldingly connected between the dash con tact and thepivot.

2. In a telegraph. transmitter, a base plate, three posts extendingupwardly from the base plate substantially in a longitudinal line nearthe transverse. center, a transversely ex tending abutment pieceadjustably secured to the first or right hand post to serve as a brake,a vibrator carrying an adjust-rule weight forming block and mounted in atransverse plane and in a line parallel with the three posts and withits free end in position to engage the abutment, a light springconnected to the vibrator at the opposite end from the weight, an armpivotally mounted near the third post in line with the vibrator andsolidly connected to the spring, an L shaped arm rigid with the first@111 and at right angles thereto, ayieldable automaticall actin dottransmittin contact secured' to Q to the vibrator in transverse linewith'the vibrator pivot, a terminal adjustably mounted in opposition tothe contact, a roller at the free end of the L-shaped arm, a combination autodot key lever mounted transversely and engaging the roller andextending forwardly and carrying a finger paddle, an adj ustable stopscrew mounted through the terminal binding post at right angles to theterminal and engaging the opposite side of the combination autodot keylever from the roller, and a dash contact adjustably mounted to engagethe combination. lever in front of its pivot and on the same side as theroller, the combination lever having a rear section mounted on avertical pivot and a front section overlapping the rear section andpivotally connected thereto and there being means for holding the twosections yieldingly in parallel positions and allowing the front sectionto move laterally away from the rear section.

3. In a telegraph transmitter, a base plate, three posts extendingupwardly from the base plate substantially in a longitudinal line nearthe transverse center, a transversely extending abutment piece adjustably secured to the first or right hand post to serve as a brake, avibrator carrying an adjustable weight forming block and mounted in atransverse plane and in a line parallel with the three posts and withits free end in position to engage the abutment, a light springvconnected to the vibrator at the opposite end from the weight, an armpivotally mounted near the third post in line with the vibrator andsolidly connected to the spring, an L-shaped arm rigid with the firstarm and at right angles thereto, a yieldable automatically acting dottransmitting contact secured to the vibrator in transverse line with thevibrator pivot, a terminal adjustably mounted in opposition to thecontact, a roller at the free end of the L-shaped arm, a combinationautodot key lever mounted transversely and engaging the roller andextending forwardly and carrying a finger paddle, an adjustable stopscrew mounted through the terminal binding post at right angles to theterminal and engaging the opposite side of the combination autodot keylever from the roller, a dash contact adjustably mounted to engage thecombination lever in front of its pivot and on the same side as theroller, the combination lever having a rear section mounted on avertical pivot and a front section overlapping the rear section andpivotally connected thereto and there being means for holding the twosections yieldingly in parallel positions and allowing the front sectionto move laterally away from the rear section, a second key leverpivotally mounted parallel with the combination lever and provided atits rear end wlth a contact, a binding post extending upwardly from thebase plate and having a contact to be engaged by the key lever contact,a spring for pressing the key lever contact away from the binding postcontact, and an adjustable stop to limit the movement of the key leverunder the action of the sprin 4-. In a telegraph transmitter, a base, akey lever pivotally mounted for horizontal movement upon said base, anarm pivoted upon said base, an L-shaped arm rigid with the firstmentioned arm and adapted to engage said key lever, a vibrator securedto said first mentioned arm and disposed at substantially right anglesto said key lever, a contact carried by said vibrator, and acorresponding contact mounted upon said base adapted to be engaged bythe vibrator contact to produce a dot or a series of dots.

5.-In a telegraph transmitter, a base, a key lever pivotally mounted forhorizontal movement upon said base, an arm pivoted upon said base, anL-shaped arm rigid with the first mentioned arm and adapted to engagesaid key lever, a vibrator secured to said first mentioned arm anddisposed at substantially right angles to said key lever, a contactcarriedby said vibrator, a corresponding contact mounted upon said baseadapted to be'engaged by the vibrator contact to produce a dot or aseries of dots, a

contact carried by said key lever, and a corresponding contact mountedupon said base adapted to be engaged by said key lever to produce adash.

6. In a telegraph transmitter, a base, a key lever pivotally mountedupon said base for horizontal movement, an arm pivotally mounted uponsaid base for horizontal movement, a vibrator carried by said arm anddisposed at substantially right angles to said key lever, a brake forsaid vibrator, spring means for normally urging said vibrator againstsaid brake, means actuated by said key lever for moving said vibratoraway from said brake against the action of said spring means, a contactcarried by said vibrator, and a corresponding contact mounted upon saidbase engageable by the first mentioned contact so as to produce a dot ora series of dot signals.

Signed at Los Angeles, in the county of Los Angeles and State ofCalifornia, this 23rd day of May, A. D. 1921.

LOUIS C. MCINTOSH. lVitnesses:

CLARENCE F. SHAW, RUTHER M. SHAW.

